Governing high-content nanoparticles distribution for architecting high-performance bamboo-structured 2024Al matrix composites
Lichaoran Guan, Kan Liu, Bin Huang, Yunpeng Cai, Nan Su, Di Zhang, Qiubao Ouyang, Yishi Su
Abstract
Fabricating high-content nanoparticle-reinforced aluminum matrix composites with balanced modulus–strength–ductility has been a long-standing challenge. Inspired by natural biostructures, an inversed bamboo configuration combined with high-content nano-dispersoids was proposed, featuring fiber-like soft bands embedded into hard matrix and exhibiting 94.88 GPa in Young’s modulus, 709 MPa in yield strength and 7.21% in elongation. The sustained strain hardening behavior led to an improved uniform elongation even at such high stress levels. The underlying mechanisms for superior mechanical properties include biostructural hetero-deformation induced (HDI) strengthening/hardening, intragranular nano-dispersoids enhanced dislocation storage of ultrafine grains and SiC/Al interfaces induced stacking faults.